code: def parse_args():
      parser = argparse.ArgumentParser(
          description="Calculate metrics for the generated sentences"
      )
      parser.add_argument(
          "--file",
          type=str,
          required=True,
          help="File path for generated text file.",
      )
      parser.add_argument(
          "--num_samples",
          type=int,
          default=None,
          help="The number of the first samples from the sample file to evaluate. "
          "By default the script uses all samples.",
      )
      parser.add_argument(
          "--num_bleu_samples",
          type=int,
          default=None,
          help="The number of samples to use from all samples for "
          "self-BLEU metric. By default the script uses all samples.",
      )
      parser.add_argument(
          "--seed",
          type=int,
          default=None,
          help="Random seed for sampling. Default seed is 0.",
      )
      return parser.parse_args()
  
file_path: gluon-nlp/docs/model_zoo/generation/calculate_metrics.py
imports: import os
  import re
  import argparse
  from nltk.translate.bleu_score import sentence_bleu
  from collections import Counter
  import operator
  import numpy
  from scipy import stats
  import random
  from tqdm import tqdm
  from functools import partial
  from multiprocessing.pool import Pool
  from gluonnlp.models.gpt2 import get_pretrained_gpt2
label_desc: Use image node_id 1 for calling a global function with example usage: parse_args() and returns: parser